Air-Conditioning Compressor or Air Conditioning System

ABSTRACT

An air-conditioning compressor for air conditioning systems, especially for motor vehicles, or an air conditioning system comprising an air-conditioning compressor. The air-conditioning compressor is connected to a high-pressure zone and a suction pressure zone. Driving chamber pressure is redirected from the driving chamber of the air-conditioning compressor, i.e. from the high-pressure zone of the driving chamber to the suction pressure zone, if necessary while a filter, particularly a dirt particle filter, is optionally located in the suction pressure zone.

The present invention relates to an air-conditioning compressor for air-conditioning systems, in particular for motor vehicles, or to an air-conditioning system having an air-conditioning compressor, the air-conditioning compressor communicating with a high-pressure zone and with a suction pressure zone, pressure being optionally returned from the drive chamber of the air-conditioning compressor, from the drive-chamber pressure zone to the suction pressure zone, and a filter, in particular a dirt particle filter, being optionally located in the suction pressure zone.

Compressors or air-conditioning systems of this kind are generally known. In this context, the problem arises that, once a certain operating time period has elapsed, the dirt particles form a so-called filter cake in the filters. Over the course of operation, the filter cake causes an increasing loss of pressure that is detrimental to the efficiency of the system.

In addition, compressors having a drive-chamber pressure return have the disadvantage that the drive-chamber pressure within the compressor is returned directly to the suction pressure zone, and, in the process, dirt particles, such as ablated material from the pressure chamber produced by the mechanical loading of the driving gear, are returned to the suction pressure zone of the air-conditioning compressor. There, the dirt particles can do damage, for example in the area of the pistons and the cylinder liners or the valve devices.

It is, therefore, an object of the present invention to devise an air-conditioning compressor or an air-conditioning system which will overcome these disadvantages.

The objective is achieved by an air-conditioning compressor for air-conditioning systems, in particular for motor vehicles, or by an air-conditioning system having an air-conditioning compressor, the air-conditioning compressor communicating with a high-pressure zone and with a suction pressure zone, pressure being optionally returned from the drive chamber of the air-conditioning compressor, from the drive-chamber pressure zone to the suction pressure zone, and a filter, in particular a dirt particle filter, being optionally located in the suction pressure zone, an additional dirt particle separator being located in the suction pressure zone. Here, the advantage is derived that dirt particles in the dirt particle separator may be collected in a collecting space and are, therefore, not able to reach the downstream filter. As a result, no filter cake that is effective to any appreciable degree is able to build up in the filter.

An air-conditioning compressor or an air-conditioning system is preferred, in which the dirt particle separator is designed as a cyclone separator, the dirt particles being separated by the action of centrifugal force along the walls of the dirt particle separator and being collected in a dirt-particle collecting device, while the purified refrigerant stream is directed to the suction pressure zone of the air-conditioning compressor.

Also preferred is an air-conditioning compressor or an air-conditioning system, in which the dirt particle separator is located in the direction of flow upstream of the filter. Also preferred is an air-conditioning compressor or an air-conditioning system, in which the dirt particle separator is located inside of the compressor housing. An air-conditioning compressor or an air-conditioning system is likewise preferred in which the drive-chamber pressure return is connected between the filter and the compressor inlet. An air-conditioning compressor or an air-conditioning system is likewise preferred in which the drive-chamber pressure return is connected between the filter and the dirt particle separator, so that the drive-chamber pressure return is also filtered. Another air-conditioning compressor or an air-conditioning system is preferred in which the drive-chamber pressure return is connected in the direction of flow upstream of the dirt particle separator, so that the drive-chamber pressure return is also cleaned of dirt particles in the dirt particle separator.

A compressor in accordance with the present invention or an air-conditioning system in accordance with the present invention has the distinguishing feature that the dirt particle separator is located outside of the compressor housing and the filter inside of the compressor housing, and the drive-chamber pressure return is connected in the direction of flow downstream of the filter, between the filter and the compressor suction-pressure zone.

Another air-conditioning compressor in accordance with the present invention or an air-conditioning system in accordance with the present invention has the distinguishing feature that the dirt particle separator and the filter are located outside of the compressor housing, and the drive-chamber pressure return is redirected in the direction of flow downstream of the filter, to the suction pressure zone of the compressor. An air-conditioning compressor or an air-conditioning system is likewise preferred in which the dirt particle separator is located outside of the housing and the filter inside of the housing, and the drive-chamber pressure return is connected in the direction of flow upstream of the filter, so that the drive-chamber pressure return flow is filtered.

The present invention is described in the following with reference to the figures, which show:

FIG. 1 schematically, in a circuit diagram, an air-conditioning compressor according to the present invention or an air-conditioning system according to the present invention;

FIG. 2 a second circuit diagram variant;

FIG. 3 a third circuit diagram variant;

FIG. 4 a fourth circuit diagram variant;

FIG. 5 a fifth circuit diagram variant;

FIG. 6 a sixth circuit diagram variant.

FIG. 1 schematically shows an air-conditioning compressor 1, a dirt particle filter 3, and a dirt particle separator 5. These three elements are located inside of the air-conditioning compressor housing, which is represented by dashed line 7. Dirt particle separator 5 functions in accordance with the cyclone operating principle, the dirt particles being separated by the action of centrifugal force along the walls of separator 5 and being collected in a dirt-particle collecting device 9. The refrigerant stream liberated from the dirt particles flows through line 11 and continues to dirt particle filter 3. Downstream of dirt particle filter 3, a connecting line 13 leads to suction-pressure chamber 15 of compressor 1, a drive-chamber pressure return 17, which originates at drive-chamber pressure zone 19, leading into connecting line 13. Drive-chamber pressure returns of this kind are generally known in the context of variable displacement compressors, and will not be described in greater detail here. Of fundamental importance to the present invention is the placement of a dirt particle separator 5 in the system in order to extract dirt particles which may be collected in a collecting space 9 and, therefore, not be able to reach downstream filter 3. Thus, it is not possible for a filter cake that is effective to an appreciable degree to build up in filter 3 which, otherwise, over the course of operation, would cause an increasing loss of pressure, that, in turn, would be detrimental to the efficiency of the system. The compressor itself and the above described devices constituted of filter 3 and dirt particle separator 5 are connected at the outlet of housing 7 to suction pressure zone 21 and, respectively, to high-pressure zone 23 of the air-conditioning system.

The circuit diagram in FIG. 2 differs from that in FIG. 1 in that a different drive-chamber pressure return 25 is now connected to a suction pressure-zone line section 27 between filter 3 and dirt particle separator 5. As a result, dirt particles from drive-chamber pressure return 25 now pass through filter 3 in any case, while the main suction-pressure flow from zone 21 additionally passes through dirt particle separator 5. Dirt particles, which originate within the drive chamber, are thus trapped in any case by filter 3 and are not carried directly to suction pressure zone 15 of air-conditioning compressor 1, as shown in FIG. 1.

The circuit diagram in FIG. 3 differs from those in FIG. 1 and 2 in that a different drive-chamber pressure return 29 is now connected to a line section 31 in suction pressure zone 21, so that drive-chamber pressure return 29 must also pass through dirt particle separator 5, and, consequently, filter 3 connected downstream thereof also no longer needs to trap these dirt particles, thereby further minimizing any pressure loss and further enhancing the efficiency of the system over the period of operation.

In another circuit diagram in FIG. 4, dirt particle separator 5 is located outside of air-conditioning compressor housing 7 in a line section 33 of the air-conditioning system. Thus, dirt particle separator 5 may be located at a separate installation site where it is easily accessible, independently of the installation location of the air-conditioning compressor, thereby facilitating maintenance of collecting basin 9. In this case, drive-chamber pressure return 17 is again provided within compressor housing 7 and communicates with connecting line 13 and, thus, with suction pressure zone 15 of compressor 1, as already illustrated in FIG. 1.

In FIG. 5, both dirt particle separator 5, as well as dirt particle filter 3 are located outside of air-conditioning compressor housing 7. Thus, a configuration of dirt particle filter 3 that is independent of the installation location of the air-conditioning compressor is additionally provided. However, for that reason, drive-chamber pressure return 17 must be provided within air-conditioning compressor housing 7 and communicate with connecting line 13 and, thus, directly with suction pressure zone 15 of the air-conditioning compressor.

In FIG. 6, in turn, only dirt particle separator 5 is located outside of compressor housing 7. Since filter 3 is again located within compressor housing 7, as illustrated in FIG. 2, drive-chamber pressure return 25 may again communicate with connecting line 27 and thus pass through filter 3, thereby enabling dirt particles from the drive chamber to be trapped therein.

Thus, the essential principle underlying the present invention is the introduction of an additional dirt particle separator 5 for extracting particles which may be collected in a collecting space 9 and, therefore, not be able to reach downstream filter 3. Thus, no appreciably noticeable filter cake is able to build up in filter 3 which, otherwise, over the course of operation, would cause an increasing loss of pressure that would be detrimental to the efficiency of the system.

It is also an aim of the present invention for drive-chamber outflow 25 or 29 to be linked to suction pressure zone 15 of compressor 1 in such a way that the compressor control characteristic is not unintentionally influenced, for example by the increasing loss of pressure across filter 3. This may be achieved, in particular, by returning the drive-chamber outflow via connecting line 29 in FIG. 3 upstream of dirt particle separator 5. It is not possible to accomplish these tasks, for example, by using dirt separators and screen filters on the discharge side of the machine.

LIST OF REFERENCE NUMERALS

-   1 air-conditioning compressor -   3 dirt particle filter -   5 dirt particle separator -   7 air-conditioning compressor housing -   9 dirt-particle collecting device -   11 line -   13 connecting line leading to suction-pressure chamber -   15 suction-pressure chamber of the compressor -   17 drive-chamber pressure return -   19 drive-chamber pressure zone -   21 suction pressure zone of the air-conditioning system -   23 high-pressure zone of the air-conditioning system -   25 drive-chamber pressure return -   27 suction pressure-zone line section -   29 drive-chamber pressure return -   31 line section in the suction pressure zone -   33 line section of the air-conditioning system 

1-10. (canceled)
 11. An air-conditioning system comprising: a high-pressure zone; a suction pressure zone; an air-conditioning compressor, the air-conditioning compressor communicating with the high-pressure zone and with the suction pressure zone; and a dirt particle separator located in the suction pressure zone.
 12. The air conditioning system as recited in claim 11 wherein the air-conditioning compressor includes a drive chamber, and further comprising a drive-chamber pressure return from the drive chamber to the suction pressure zone.
 13. The air conditioning system as recited in claim 12 further comprising a filter located in the suction pressure zone.
 14. The air conditioning system as recited in claim 11 further comprising a filter located in the suction pressure zone.
 15. The air conditioning system as recited in claim 14 wherein the filter is a dirt particle filter.
 16. The air-conditioning system as recited in claim 11 wherein the dirt particle separator is a cyclone separator and the air conditioning compressor includes a suction-pressure chamber, and further comprising a dirt-particle collection device, dirt particles being separated by an action of centrifugal force along walls of the dirt particle separator and being collected in the dirt-particle collecting device, while a resultant purified refrigerant stream is directed toward the suction-pressure chamber.
 17. The air-conditioning system as recited in claim 14 wherein the dirt particle separator is located upstream of the filter.
 18. The air-conditioning system as recited in claim 11 wherein the compressor includes a housing, the dirt particle separator being located inside of the compressor housing.
 19. The air-conditioning system as recited in claim 18 wherein the air-conditioning compressor includes a drive chamber and suction pressure chamber, and further comprising a drive-chamber pressure return from the drive chamber to the suction pressure zone and a filter in the suction pressure zone, the drive-chamber pressure return being connected between the filter and the compressor suction-pressure chamber.
 20. The air-conditioning system as recited in claim 18 wherein the air-conditioning compressor includes a drive chamber, and further comprising a drive-chamber pressure return from the drive chamber to the suction pressure zone and a filter in the suction pressure zone, the drive-chamber pressure return being connected between the filter and the dirt particle separator.
 21. The air-conditioning system as recited in claim 18 wherein the air-conditioning compressor includes a drive chamber, and further comprising a drive-chamber pressure return from the drive chamber to the suction pressure zone, the drive-chamber pressure return being connected upstream of the dirt particle separator.
 22. The air-conditioning system as recited in claim 11 wherein the air-conditioning compressor includes a housing, a drive chamber and a suction-pressure chamber, and further comprising a drive-chamber pressure return from the drive chamber to the suction pressure zone and a filter in the suction pressure zone, the dirt particle separator being located outside of the compressor housing and the filter inside of the compressor housing, and the drive-chamber pressure return being connected downstream of the filter between the filter and the suction-pressure chamber.
 23. The air-conditioning system as recited in claim 11 wherein the air-conditioning compressor includes a housing, a drive chamber and a suction-pressure chamber, and further comprising a drive-chamber pressure return from the drive chamber to the suction pressure zone and a filter in the suction pressure zone, the dirt particle separator and the filter being located outside of the housing, the drive-chamber pressure return being connected downstream of the filter between the filter and the suction-pressure chamber.
 24. The air-conditioning system as recited in claim 11 wherein the air-conditioning compressor includes a housing, a drive chamber and a suction-pressure chamber, and further comprising a drive-chamber pressure return from the drive chamber to the suction pressure zone and a filter in the suction pressure zone, the dirt particle separator being located outside of the housing and the filter inside of the housing, and the drive-chamber pressure return being connected upstream of the filter.
 25. The air conditioning system as recited in claim 11 wherein the air-conditioning system is a motor vehicle air-conditioning system. 